1,2-dialkyl-3,5-diphenylpyrazolium salts

ABSTRACT

This invention is (1) synergistic combinations of a 1,2-dialkyl3,5-diphenylpyrazolium salt and a 2,4-dichlorophenoxy acetic acid or the salts and esters thereof, or 4-chloro-2-methylphenoxy acetic acid or the salts or esters thereof useful as herbicides; (2) a salt of a 1,2-dialkyl-3,5-diphenylpyrazolium cation and certain halophenoxy acetate anions useful as herbicides and (3) the synergistic combination of 1, above, with the salt of 2, above, present.

1 1,2-DIALKYL-3,S-DIPHENYLPYRAZOLIUM SALTS [75] lnventor: RichardWilliam Feeny, Hightstown,

[73] Assignee: American Cyanamid Company,

Stamford, Conn.

[22] Filed: Nov. 17, 1972 [21] Appl. No.: 307,670

[52] US. Cl. 260/311, 71/92, 260/310 R [51] Int. Cl C07d 49/18 [58]Field of Search 260/310 R, 311

[56] References Cited OTHER PUBLICATIONS Timofeeva et al., J. Gen Chem.,USSR, Vol. 40, pages 2057-2062, (1970). Elguero et al., Bul. Soc. Chim.,France, 1969(5),

[ Feb. 18, 1975 pages 1,6871,698.

Nye et al Tetrahedron, Vol. 28, pages 455462, (1972, Feb. 1972).

Takeda Chem. lnd., Chem. Abstract, Vol. 61, C01- umns 16,073l6,074,(1964),

Primary ExaminerNatalie Trousof Attorney, Agent, or Firm-H. G. Jackson[57] ABSTRACT This invention is (1) synergistic combinations of a 1,2-dialkyl-3,S-diphenylpyrazolium salt and a 2,4- dichlorophenoxy aceticacid or the salts and esters thereof, or 4-chloro-2-methylphenoxy aceticacid or the salts or esters thereof useful as herbicides; (2) a salt ofa 1,2-dialkyl-3,S-diphenylpyrazolium cation and certain halophenoxyacetate anions useful as herbicides and (3) the synergistic combinationof 1, above, with the salt of 2, above, present.

3 Claims, N0 Drawings 1 1 'P H N LP RALQLIQM. SALTS CROSS REFERENCE TORELATED APPLICATIONS l-Ierbicidal activity of some of thel,2-dialkyl-3,5- diphenylpyrazolium salts useful in the combinations ofthis invention is reportedin the Klingsberg and Walworth copending US.Pat. application Ser. No. 307,672, filed of even date.

BACKGROUND OF THE INVENTION for control of broadleaf weeds, suchcompounds have demonstrated no discernible herbicidal effect on wildoats (Avena spp.) at rates of application normally used for broadleafweed control in the presence of economic crops. By itself, thisobservation would not be considered particularly important, since onewould normally expect that a compound could be found which would provideadequate wild oat control, and that a mixture of said wild oat herbicideand the phenoxyacetic acid, ester or salt, would then provide effectivecontrol for both wild oats and broadleaf weeds. Unfortunately, however,the problem is not quite so simple.

Wild oats (Avena spp.) are of the family Graminae, the same family inwhich the small grains, such as wheat and barley are classified. Theyreact to most chemicals in the same manner as the othermembers of thefamily, and thus are particularly difficult to control in the presenceof economically important grain crops in said family. It is not,therefore, surprising that a considerable effort was required to findseveral chemicals which provide the selectivity. required to achievewild oat control in the presence of the grains mentioned. The mostwidely accepted of these are 4-chloro-2- butynylN-(3-chlorophenyl)carbamate (BARBAN) and the ethyl ester ofN-benzoyl-N-(3,4- dichlorophenyl)alanine (SD-30053). They are veryeffective wild oat control agents when used alone, but unfortunately,when they are combined with the most widely accepted of the systemic orhormonal broadleaf herbicides utilized in the cultivation of smallgrains, i.e. 2,4-D, MCPA and the esters and salts thereof, the compoundsare antagonistic and wild oat control is lost.

These findings are well documented in the literature in articles, suchas have appeared in Weeds Today, pg. 13, July of 1970, or in thefollowing articles: Studies of Barban Selectivity for Wild Oat in Wheat,R. W. Neidermyer, Fargo, North Dakota, Dissertation Abstr. Intern. 3l,No. 11, 638 3-B-84-B, 197l; Antogonistic Effect of 2,4-D Amine andSD-30053 on Wild Oats," D. R. Colbert and A. P. Appleby, Corvallis,Oregon, Res. Prog. Rept. West. Soc. Weed Sci., March, 1972, 118-]19;SD-30053 Plus Broadleaf Herbicides, John D. Nalewaja, The ResearchReport of North Central Weed Control Conference 197], pgs. 32-33; InGeneral, Members of the Grass Family are Resistant to 2,4-D While MostBroadleaf Plants are Susceptible,"

, Weed Control, Robbins, Crafts and Razner, page 9,

2 1 McGraw Hill, 2nd Edition, 1952; and Wild Oats are Resistant to2,4-D," Weed Control as (1 Science, Kling: man, page 388, Wiley, 1961.

In the light of the fact that few compounds have been found whichprovide selective control of wild oats in the presence of grass graincrops, and further that the most widely accepted of those which areselective are inactivated when combined with the broadleaf controlagents, 2,4-D and MCPA, it is surprising to find a compound(i.e. al,2-dialkyl-3,5-di-phenylpyrazolium salt) that is selective for controlof wild oats and also exhibits enhanced wild oat activity when used incombination with systemic or hormonal broadleaf herbicides. i.e. 2,4-D,MCPA or the esters, salts or mixtures thereof.

SUMMARY OF THE INVENTION The invention is synergistic herbicidalcombinations comprising (a) a l,2 dialkyl-3,S-diphenylpyrazolium salt ofthe formula:

(VXQ Y =e l r Y Z NN Z R4 0 O ssLts,

wherein R is Cl or methyl; R is hydrogen or methyl;

R is OR,, or --OM; R is hydrogen, alkyl C -C (preferably methyl, ethyl,isopropyl, butyl, pentyl, ethylhexyl, octyl or isooctyl), alkoxyalkyl.CC (preferably butoxyethyl or Z-butoxyethyl) and tetrahydrofurfuryl; andM is a alkali metal ion (preferably Na or )a or -I-IN (I-I),,(R OII),,;R R and R are hydrogen or alkyl C,C.,; R is alkylene C -C n is aninteger 0,

l or 2; n is an integer 1,2 or 3; and the sum of n and where R1, R R RY, Y, Z and Z are as, described above. These new compounds are alsouseful herbicides and may be present in the synergistic herbicidalcombination, above.

Suitable halogen substituents for formula (1) compounds include, forexample, fluoro, chloro, bromo and iodo. The chloro, fluoro and bromogroups are preferred. Suitable anions include, for example, halides,such as chloride, bromide or iodide; acetate; sulfate, hydroxide;hydrogen sulfate; methyl sulfate; benzene sulfonate; C -C alkoxy benzenesulfonate; C -C alkyl benzene sulfonate, preferably a toluene sulfonate,such as p-toluene sulfonate; nitrate; phosphate; carbonate; hydrogencarbonate; chlorate; thiocyanate; CF04 alkane sulfonate; perchlorate;-Brl and This invention also relates to a method for the postemergencecontrol of wild oats (Avena spp., such as A. fatua, A. sterilis and A.ludoviciana) and undesirable broadleaf plants, and involves theapplication of a herbicidally effective amount of l the synergisticcombination, (2) the salt or (3) a composition containing both, to thefoliage of said undesirable plant species.

PREFERRED EMBODIMENTS In accordance with this invention, the synergisticherbicidal combination comprising the l,2-dialkyl-3,5 diphenylpyrazoliumsalt and the chlorophenoxyacetic acid, ester or salt or the salts of thepyrazolium cation and the halophenoxyacetate anion, is generallydispersed in water and applied as an aqueous spray to the foliage of theundesirable plants. Water soluble salts of both the pyrazolium and thehalophenoxy compounds can be dissolved in the water and applied as suchto the foliage of the undesirable plants. Where desired, a surfactant,spreader, sticker, or the like, can also be added to the solution, andaddition of a surfactant, such as a linear alkyl polyoxyethylene ether,to the mixture is generally preferred. The pyrazolium salts and thephenoxy compounds may also be individually prepared as wettable powderformulations, emulsifiable concentrates, water miscible concentrates, orthe like, and mixed in the spray tank in the field. Any of thecommercially available phenoxy acetic acid, esters or salt formulationsmay, of course, be used. Typical ester for- Typical wettable powderformulations of the pyrazolium salt and the halophenoxyacetic'acid,ester or salt, contain from about 25% to 75% by weight of the activecompound, to 71.5% by weight of a finely divided carrier, such asattapulgite, kaolin, silica, or the like, 1.5% to 3% by weight ofasurfactant, such as sodium N-methyl-N-oleoyltaurate ester ofsodiumisothionate, alkyl phenoxy polyoxyethylene ethanol, or the like, and 2%to 3% by weight of a dispersant, such as a highly purified sodiumlignosulfonate, naphthalene sulfonic acid condensate, or the like.

For effective control of undesirable plants, the synergistic herbicidalcombination is normally applied in suf' ficient amount to provide fromabout 0.25 pound to 2.0 pounds per acre, and preferably. 0.50 pound to1.0 pound per acre, of the pyrazolium cation, and from about 0.1 3 poundto 1.0 pound per acre, and preferably 0.25 pound to 0.50 pound per acre,of the phenoxyacetic acid equivalent as the acid, ester or salt.

While the synergistic herbicidal combinations of this invention havebeen indicated to be useful for controlling wild oats andbroadleaf weedsin the presence of the agronomically important crops, wheat and barley,the combinations are also found to be useful for the control of theseundesirable plant species in the presence of other crops, such as rye,flax and peas.

The invention is further demonstrated by the examples below, which arepresented as illustrative and are not to be construed as limitative.

The postemergence herbicidal activity of the sy nergistic combinationsof the invention is demonstrated by the data reported in Tables I, IIand Ill, below.

EXAMPLE 1 In the tests of Table I, wild oats (Avena falua) are growninflats in the greenhouse until they reach the four-leaf stage. They arethen sprayed with an aqueous solution containing a sufficient amount oftest compound to provide from about 0.15 pound per acre to 0.60 poundper acre of pyrazolium cation. For comparison, test compounds are usedalone and in combination with 4-chloro-2-methylphenoxyacetic acid(MCPA), added in sufficient amount to provide 0.25 pound per acre ofsaid compound.

All test solutions are prepared in such a manner as to contain about0.1% by weight of thebiodegradable non-ionic linear alkylpolyoxyethylene ether marketed by Union Carbide Corporation as Surfel4884. Untreated plants are used as controls, and four weeks aftertreatment the foliage of all plants is harvested and weighed.

. Data obtained are reported in Table 1 below, where it can be seen thatthe addition of 4-chloro-2-methylphenoxyacetic acid to solutionscontaining a 1,2- dialkyl-3,5-diphenylpyrazolium salt markedly enhancedwild oat control; whereas, addition of 4-chloro- 2-methylphenoxyaceticacid to the commercially available wild oat herbicide,4-chloro-2-butynyl N-(3-chlorophenyl)carbamate, nullifies wild oatconlinear alkyl polyoxyethylene ether. trol.

- TABLE 1 Effect of MCPA on the Wild Oat Activity of Test Compounds 7tInhibition Pound of Wild Oat foliage Weight Per No MCPA MCPA added atTreatment Acre Added V4 lb./Acre** Water 0 0 1,2-Dimethyl-3,S-diphenylpyrazolium toluenesulfonate 0.15" 45 621.2-Dimethyl-3,5-diphenylpyrazolium toluene- TABLE l- Continued Effectof MCPA on the Wild Oat Activity of Test Compounds 7: inhibition Poundof Wild Oat foliage Weight Per No MCPA MCPA added at Treatment AcreAdded A lb./Acre" sulfonate 030* S3 73 I,2'Dimethyl-3,S-diphenylpyrazolium chloride 060* 53 69 4-Chloro2butynylN-(3- chlorophenyUcarbamat'e 0.50 59 Rate given in pounds per acre forpyrazolium cation. Rate given in pounds per acre of acid equivalentsapplied as the dimethylamine salt.

EXAMPLE 3 EXAMPLE 2 Wild Oat Control in the Presence of Hard Red SpringWheat In these tests, wild oats (Avena sp.) at the four-leaf stage,growing in the presence of hard red spring wheat, is sprayed with anaqueous solution of the test compound,l,2-dimethyl-3,S-diphenylpyrazolium methylsulfate, in sufficient amountto provide 0.5 pound per acre of active cation or with an aqueoussolution containing 0.5 pound per acre of the active cation plus 0.375pound per acre of 4-chloro-2-methylphenoxy acetic acid.

Each solution also contains 0.5% by weight of the surfactant Surfel4884, a linear alkyl polyoxyethylene ether, marketed by Union CarbideCorporation. Six weeks after treatment, the fields are examined and thepercent control of wild oats is determined. Four replicates pertreatment are used and reported in Table 2 below.

Wild Oat Control in the Presence of Waldron Wheat In these tests,Waldron wheat is seeded in early May. Five days later, and several daysprior to wheat emergence, wild oats (Avena spp.) emerge. When the wildoats develop to the four-leaf stage, selected plots are sprayed withaqueous solutions containing 1,2-

-dimethyl-3,5-diphenylpyrazolium methyl sulfate or said compound plus2,4-dichlorophenoxy aceticacid (2,4- D).

Applications are made in such a manner as to provide 8 or 16 ounces peracre of the active pyrazolium cation compound alone and in combinationwith 6 ounces per acre of 2,4-dichlorophenoxy acetic acid (2,4-D).

Each solution also contains 0.5% by weight of the surfactant. Surfel4884, the linear alkyl polyoxyethylene ether marketed by Union CarbideCorporation. Eight weeks after treatment the plots are rated for wildoat and wild mustard control. Data obtained-are reported below in TableTABLE III Wild Oat and Wild Mustard Control in the Presence of WaldronWheat 72 inhibition (0400) Rate given as pound per acre of pyrazoliumcation. Rate given in pounds per acre of acid equivalents applied as thedimethylamine salt.

TABLE 2 Control of Pound Wild Oats Per Replicates Treatment Acre* I itIII IV Ave.

l,2-Dimethyl-3,S-diphenylpyrazolium methyl sulfate 0.50 40 40 50 451,2-Dimethyl-3.S-diphenylpyrazolium methyl sulfate 0.50 plus4Chloro2-methylphenoxy 60 79 acetic acid" 0.375

* Rate given as pound per acre of pyrazolium cation. Rate given inpounds per acre of acid equivalents applied as the dimethylamine salt. 7g V H W Results comparable to those in Tables I, ii, and iii areobtained when other synergistic combinations of the invention are used.

EXAMPLE 4 Preparation of l,2-Dimethyl-3,S-diphenylpyrazolium2,4-dichlorophenoxyacetate l,2-Dimethyl-3,S-diphenylpyrazolium methylsulfate was converted by ion exchange chromatography to the pyrazoliumhydroxide. This was then titrated (H O solution) with2,4-dichlorophenoxyacetic acid. Solid 2,4-D was added and went intosolution after a very short time. The pH of the solution was monitoredusing a pH meter. Addition of the acid was stopped at pH 7 (initially pHwas 12 to 13). This H O solution was kept at room temperature for 48hours. The pH was then ap- Since the diketone and hydrazine compoundscomproximately 8. An additional amount of acid was added him inequimolar quantities, it is preferable to maintain until pH 7 was againobtained. After 24 hours, pH held the molar ratio of reactants at about1:1; however, a at 7 slight excess (up to about 10%) of either reactantmay The H O solution 'was evaporated to a yellow oil and be used.

then azeotroped with toluene/acetone several times. The ring-formingreaction between the hydrazine or V Hexane was added with to dryacetone. The oil alkyl hydrazine and the diketone is preferably carriedsolidified to a white solid, was filtered, washed with out by combiningthe reactants in asolvent and heating hexane/acetone and dried. 7.0Grams, melting point to the reaction temperature. Suitable temperaturesare 152C. to 154C, ofa lemon yellow solid was Obtained. in the range offrom about 70C. to about 150C. and,

Analysis Calculated for N O Cl C H C, 63.97; H, preferably, between 80C.and 120C. Suitable solvents 4.72; N, 5.96. Found: C, 63.67; H, 4.69; N,5.90. The include, for example, aprotic solvents, such as, xylene,compound is useful as a herbicide. 25 toluene, benzene, pyridine, DMSO,DMF, and the like, or protic solvents, such as, C C, alcoholspreferably,

EXAMPLE 5 nand iso-propanol. Where the latter solvents are em-Preparation of l,2-Dimethyl-3,S-diphenylpyrazolium ployed, high rates ofconversion are obtained at tem- 4-chloro-2-methylphenoxyacetateperatures in the range of 80C. to 85C.

l,2-Dimethyl-3,S-diphenylpyrazolium hydroxide in a Where hydrazine isemployed in the initial condensa- H O solution was titrated with4ChlorO-2- tion reaction, alkylation of the resulting pyrazole is acylpyacid known herblcomplished with conventional alkylating agents,prefercide until pH 7 was obtained and retained for 48 hours. bl i hpresence f an a id acceptor, h as an MCPA 1 added 115 a Solid and slowlydissolved 'kali metal hydroxide or alkoxide. Suitable bases in- The H Osolution was evaporated to a lowvolume (oil) clude, for example, sodiummethoxide, sodium hydroxand toluene/acetone azeotroped several times. Hexane ide, and the like. I (5% acetone) was added and the oil solidifiedto a light 50 The alkylation reactions are preferably conducted inyellow solid and was filtered, washed with hexane and the presence ofasolvent, such as toluene, methylisobudried. 6.5 Grams, melting point138C. to 140C. Of a tylketone, nor iso-propanol or an aqueous alcoholsolight yellow solid was obtained. lution, such as a mixture ofn-propanol and water.

Analysis Calculated for 2 a 2e 2s 3- Suitable alkylation reagentsinclude, for example, 5- FOImdI N, The 55 alkyl halides, alkyl acetates,alkyl sulfates, alkyl nicompound is useful as a herbic trates, alkylphosphate, alkyl carbonates, alkyl hydro- The remaining examplesillustrate the Preparation of gen sulfates, alkyl methyl sulfates'andalkyl toluene sul- Various pyrazolium $3115 Useful in the synergisticfonates; wherein, said alkyl groups are in the range of combinations ofthe invention. The pyrazolium salts (1) f C C to id the appropriatea|ky| Substituem are conveniently prepared by first condensing the api hf l compoumyv Propriate dikfatone with hydrazine or a 1- 4 lower Thepyrazole and alkylating reagent combine on an alkyl hydrazme to form thecorresponding equimolar basis. However, it is often preferred toemdiphenylpyrazole. Thereafter, said pyrazole is'alkylated ploy anexcess of the alkylating agent Optimum reac lQfQQTUllF. Ql -1 l? PYIEBUPT. 5.9 tion conditions for effecting the alkylations will vary Wherehydrazine is employed in the condensation, 5 depending on the reactantsemployed. Reaction is efalkylations are effected at thel and 2positions. Where fected by combining the alkylating agent, the pyrazolea lower alkyl hydrazine is employed in the initial conand, preferably,the acid acceptor and solvent. Reacdensation, alkylation is effected atthe 2 position. 7 tion often occurs at room temperature. If not, thereaction mixture is heated until the reaction occurs. Where thealkylating reagents employed are volatile, such as, methyl chloride, thereaction is preferably conducted in a sealed vessel under pressure, toavoid loss of the reactants.

Quaternization of the l-alkylpyrazole is effected by reaction thereofwith at least an equimolar quantity of an alkylating agent, such asthose mentioned above.

This reaction is preferably conducted in the presence of a solvent, suchas, a lower alcohol C -C a ketone, such as, acetone, methyl isobutylketone, methyl ethyl ketone or cyclohexanone; a chlorinated hydrocarbon,such as, chloroform; an ether, such as, diethyl ether, methyl ethylether or di-n-propyl ether; a molar aprotic solvent, such as, dimethylsulfoxide or dimethylformamide; or, preferably, an aprotic solvent, suchas, xylene, toluene or benzene.

The quaternization is effected by mixing the reactants and solvent atternperatnres maintained between 35C. and 150C, preferably between 50C.and 125C.

Since the l-alkylpyrazole and alkylating reagent combine in equimolarquantities, it is preferred to employ a 1:1 molar ratio thereof;however, an excess of either reagent may be employed.

As in the previously discussed alkylation reaction,

where the alkylating agent is volatile at the temperatures used, such asin the case of methyl chloride, it is preferred to use a sealed pressurevessel to conduct the reaction.

Where the diketone selected is asymetrically substituted and R, differsfrom R in the formula (1) compound to be produced, a mixture of isomerswill result from the above synthetic scheme. In such cases, it isgenerally expedient to employ the isomer mixture in the herbicidalprocesses of the present invention. Where their separation is desired,however, it may be effected by conventional separation techniques, suchas, for example, by fractional crystallization.

In carrying out the above ring closure and alkylation reactions, it maybe expedient to initially form a salt having an anion other than thatwhich it is desired to employ in the herbicidal processes of the presentinvention. I g l The exchange may be effected by treating the initiallyformed salt with an ion exchange resin. Among the suitable ion exchangeresins, one may mention a strong base organic anion exchanger.Illustrative exchangers employ quaternary ammonium salts. Where theresin is supplied as the salt of an anion other than that desired, it ispretreated with an aqueous solution of a salt of the desired anion. Forexample, if the resin is supplied as a quaternary ammonium chloride andit is desired to produce a pyrazolium nitrate, one would pretreat theresin with an aqueous solution of sodium nitrate. V H

Other optional subsequent modifications of the anion in the pyrazoliumsalt may be effected. For example, a pyrazolium chloride may beconveniently converted to the corresponding bromide or iodide bytreatment with NaBr or Nal, respectively, in a solvent, such as acetone.A pyrazolium salt, such as the chloride, may be con.- verted to thecorresponding perchlorate by treatment of an aqueous solution of saidsalt with perchloric acid. However, the pyrazolium perchlorates differmeasurably from other pyrazolium salts in that they exhibit extremelypoor water solubility and are substantially EXAMPLE 6 Preparation of1-Methyl-3,S-diphenylpyrazole (VII) fYQ vrn

545.0 Grams (2.43 moles) of dibenzoylmethane and 533 ml. of pyridine arestirred together and heated to C. 112 Grams (2.43 moles) ofmethylhydrazine are then slowly added t'o the mixture and a strongexothermic reaction ensues necessitating cooling of the mix,- ture witha water bath. When addition is complete, the mixture is heated to refluxand maintained in this condition for 40 minutes. The mixture is thencooled to 30C., poured into 19 liters of 3N HCl, filtered, and the solidcollected. This is reslurried in 198 grams (2.43 moles) of sodiumacetate dissolved in 19 liters of water. The mixture is filtered, waterwashed and air dried to give 535 grams of product, 94.5% yield, havingmelting point 58C. to 59C.

Following the above procedure and substituting ethylhydrazine,n-propylhydrazine,. isopropylhydrazine, sec-butylhydrazine, n-butylhydrazine, or isobutylhydrazine for methylhydrazine in theabovereaction yieldsrespectively: 1-ethyl-3,5-diphenylpyrazole;l-npropyl-3,S-diphenylpyrazole; l-isopropyl-3,5- diphenylpyrazole;l-sec-butyl-3,S-diphenylpyrazole; l-n-butyl-3,S-diphenylpyrazole; andl-iso-butyl-3,5- diphenylpyrazole.

EXAMPLE 7 Reaction of the appropriately substituted dibenzoylmethanewith the appropriate alkylhydrazine under the conditions of Example 6results in the preparation of l-alkyl-3,5-substituted diphenylpyrazoles.Graphically, the process may be illustrated as follows:

0 O f ALOHA l 1 Among the compounds which can be prepared by thisreaction are those identified in the Table below. For compounds in thisTable, Y and Z are both hydrogen.

Preparation of 1,2-Dimethyl-3,5-diphenylpyrazolium p-toluene sulfonateCH3SO3CH3' N-1II CH3 (XII) (XIII) CH3 CH:

, XXIV) A L.

400 Grams (1.71 moles) of l-methyl-3,5- diphenylpyrazole is dissolved in2,100 ml. of xylene and the solution thus prepared dried by azeotropicdistillation. The solution is cooled to 70C. and 318 grams (1.71 moles)of methyl-p-toluene sulfonate is added. The mixture is then refluxed forone hour and cooled causing the product to crystallize. When the mixtureis cooled to C., 1,000 ml. of acetone are added. The mixture isfiltered, washed with acetone, and dried in vacuo yielding 495 grams(69%) of product having a melting point of 177C. to 178C.

EXAMPLE 9 the mixture, and the mixture heated to reflux. After refluxingfor 12 hours, the mixture is cooled and filtered. The filtrate is againrefluxed and as product forms, it is separated from the mixture byfiltration. The total amount of solid recovered is 1.21 grams, 15%yield, having a melting point of 167C. to 169C.

EXAMPLE 10 Preparation of l,2-dimethyl-3,S-diphenylpyrazolium hydrogensulfate and methyl sulfate 5.0 Grams'of 1-methyl-3,5-diphenylpyrazole isdissolved in 30 ml. ofdry xylene with heating and constant stirring. Thesolution is cooled to C., and 2.78 grams of dimethyl' sulfate is. addedin 10 ml. of xylene. The mixture is then heated to C. for 6 hours andallowed to cool. After cooling, the mixture is filtered. The solid whichis recovered is stirred with dry acetone and the mixture filtered. Thisyields 3.91 grams of the methyl sulfate, 50.7% yield, having a meltingpoint of 146C. to 148C.

The filtrate is then evaporated to remove acetone and the remainingresidue is collected. The residue weight of 1.23 grams, 16.6% yield, isthe desired hydrogen sulfate having a melting point of 188C. to 1 89.5C.

EXAMPLE 11 Following the general procedures of Examples 8,9 or 10substituting the appropriately substituted l-alkyl- 3,5-substituteddiphenylpyrazole for 1-methyl-3,5- diphenylpyrazole and the appropriatealkyl-p-toluene sulfonate, alkyl halide or alkyl sulfate for themethyl-ptoluene sulfonate, methyl iodide or dimethyl sulfate, yields thecorresponding 1,2-dialkyl substituted 3,5- diphenylpyrazolium salt. Thereaction is graphically illustrated below:

5; I Y Y Alkylating Agent Z III-N Z wherein R R X, Y, Y, Z, Z and m areas described above for (1). Among the compounds which can be prepared bythis reaction are those identified in the table below, where Y and Z areboth hydrogen TABLE V.REACTANTS AND PRODUCTS Melting Y Z R] Alkylatlngagent R: X point. 0

Cl (3) CH3 CH3 C7H7S03 CHz- -S O OCH;

B1 (4) II Clla I (elln (M17303 t Cll; S()g()C:ll5

CH3 (4) 11 CH; (ClhhSOf (.lln (3113804 174470 OCH; (3) H CH3 CH: C1H SO3CH S O2--0CH3 C1 (3) Cl (4) CH3 CH3]: CH I B1 (3) B! (5) C2H5 CzHsI CzHsI CH: (2) CHa (6) CH: n-CaHyI C3H -n I a H (CHahSQt CH3 CHaSO4 -122TABLE V.REACTANTS AND PRODUCTSContinue-.d

Melt Y Z R1 Alkylating agent R; X point cm (a 00111 (4) 6."... iC;,H Br7' w 7 0.1114 13; V V V 7 Cl (4) II C4Ha-8BC CH3]: CH I C1 (4) H C4Hr$sec-CtH Br C H -sec Br CH3 (4) Cl (3) CH3 C1131 CH3 I OCHz (4) H CH3(CH3)2SO4 CH3 CH3SO4 137-1385 OCH; (4) H CH3 CH3 C1H7SO1 1.27.5-129 CH35 OaCHa H H CH3 (C HshSOt C2115 C H5SO1 109-111 CH3 (4) H CH3 CH1C7H7S02 150-151. 5

CH3 S 020 CH3 EXAMPLE l2 l5 EXAMPLE 16 Preparation of3,5-Diphenylpyrazole 22.4 Grams (0.10 moles) of dibenzoylmethane in 200ml. of isopropyl alcohol are heated to reflux (approximately 85C.), andto this is added hydrazine hydrate at a rate sufficient to maintainreflux. Thirty minutes after addition, the reaction is complete. Thereaction mixture is permitted to cool and is then poured into water. Thedesired product as a fine white solid precipitates and is filtered,washed with cold water and dried, yielding 22.1 grams of product,melting point 198.5C. to 200.5C.

EXAMPLE 13 Preparation of l-Methyl-3,S-diphenylpyrazole 5.0 Grams ofdibenzoylmethane in 40 ml. of isopropanol is heated to 50c. Thetemperature of the reactionmixture is then raised to about 85C; and 10.5grams of methyl hydrazine in ml. of isopropanol added thereto. Themixture is heated at this temperature for minutes, then cooled and coldwater added thereto. A white solid precipitate forms and is filtered,washed and dried to yield 5.22 grams ofprod uct having a melting pointof 595C. to 60C., 99+% yield.

EXAMPLE 14 Preparation of 1,2-Dimethyl-3,S-diphenylpyrazoliumperchlorate 4.7 Grams (0.02 moles) of 1-methyl-3,5-

diphenylpyrazole is added to a solution of methyl chloride, 1.5 grams(0.03 moles) in ml. of n-propanol maintained at C. The mixture is thenheated to 100C. and evaporated to a bright green 011. On addition ofhexane and cooling, the pyrazolium chloride as a green solidprecipitates. The solid is washed with water and dissolved in 60 ml. ofH 0 and then HClO, added. The pyrazolium perchlorate as a whiteprecipitate forms. it is filtered, washed with water and dried to yieldthe desired product.

EXAMPLE 15 Preparation of l,2-Dimethyl-3,S-diphenylpyrazoliumMethylsulfate 375 Grams (1.6 moles) of 1-methyl-3,5-

diphenylpyrazole is dissolved in 1850 ml. of dry xylene 60 and heated to60C. 208.13 Grams 1.65 moles) of dimethylsulfate in 150 ml. of dryxylene is then added and the temperature of the reaction mixture raisedto 105C. to 110C. and maintained there for 7.5 hours. The mixture isallowed to cool and then filtered. A brown solid is recovered, washedwith xylene and then dry acetone to give the product in 88% yield,having a melting point of 155C. to 157C.

Preparation of 1,2-Dimethyl-3,S-dipheriylpyrazolium .l midsww A glasscolumn is packed with a commercial grade of 20 a trimethyl benzylammonium chloride, strong base organic anion exchange resin. The resinis washed thoroughly with an aqueous sodium bromide solution of 1 Nconcentration until Br ion is detected in the eluent. Then an aqueoussolution of 1,2-dirnethyl-3,5-

5 diphenylpyrazolium p-toluene sulfonate is passed down the column at aslow rate. The eluent is concentrated in vacuo, leaving the desiredproduct as a residue after drying with a melting point of 188C.-189C.

Analysis: Calcd. for C HnN Brz C, 62.01; H, 5.22; 30 N, 8.54; Br, 24.22.Found: C, 61.98; H, 5.30; N, 8.54;

EXAMPLE 17 Following the general procedure of Example 16 35 above,substituting the appropriate sodium salt for the sodium bromide usedtherein and the appropriate pyrazolium p-toluene sulfonate for that usedtherein yields the compounds having the following formula andsubstituents set forth in the table below.

diphenylpyrazolium p-toluene sulfonate (10.0 g.) in 500 ml. of water isadded a 20% aqueous solution of "perchloric acid with vigorous stirring.The product separates immediately as a white solid. It is collected byfiltration, washed with water and dried to give 8.3 g. of

the desired product having a melting point of 183C.-l 84C., and thefollowing elemental analysis:

Calcd. for C, H -,ClN O.,: C, 58.75; H, 4.92; N, 8.05. Found: C, 58.21;H, 4.84; N, 7.95.

3,867,403 15 V V 16 EXAMPLE l9 7 EXAMPLE 21 Following the general ringclosing procedure of Example 4 and the alkylation procedure of Example9.

Following the general Procedure of Example 18, employing methylhydrazineand the appropriate dikestituting the appropriate pyrazolium lit-toluSUlfO- 5 tones and alkylating agents yields the pyrazolium salts natefor that used therein results in the formauon f thef h f ll i f l h i hb i m Set perchlorates set forth in the table below. forthjn the tablebelow.

10 Y e i Y 010.- Y i i Y H Z 1 1 R1 R2 1 R1 R2 7 n1 TABLE VIISubstituents Melting pcint X Y Y Z Z R1 R2 C.)

H Cl 4 H H CH CH 177.5-170 -0 s OZ-QCHS a a OSOaCH3 H 01 (4) H H CH3 CH3340 0SOa-CH; H Cl (4) H H CH; CH: 217-210 C104 H 01 (4) H H CH1 CH1 1365-138 0104 H H H H CH1 01111-17 145-140 5 C2H5O-SO:O H H H H CH; C2115100-111 CHs02-0 H Cl (4) H 11 (H3 CH: 130. 5-138 CHaO-SOO H CH3 (4) 11 HCH1 CIT: 107-110 0101 H C1 3) 11 H CH3 0111 117-100 C101 H 01(2) H H CH1CH3 124-128 CHaO-SOg-O H CH3 (3) H H CH; CH; 07-100 0104 H CH3 (2) H HCH3 CH3 160-170 C101 H cHao (4) H H CH: 01-11 112-150 CHs020 H C1 (3) HC1 (5) CH1 CH1 10 104 HSOq H 01 (2) H H CH1 CH3 CH3OSO2-O H CH; (2) H HCH3 CH3 C104 C1 (3) H 01 (5) H CH3 CH3 183-185 CHaOSO2O C1 (3) H 01 (4)H CH3 CH3 152-153 1 Purple gum. 2 Brown gum.

TABLE VI 7 I claim:

7 V V V .substiwems Acompound of the formula: V

Z R, R2 mp. C.

H 11 C11 ou 145-1405 EXAMPLE 20 4O 1l D e i CH 0 c1 Preparation ofl,2-Dimethyl-3,S-diphenylpyrazo'lium O triiodide To a solution of 2.0grams (0.0053 moles) of 1,2- dimethyl-3,S-diphenylpyrazolium iodidein-lOO ml. of aqueous ethanol (1:1) was added 1.34 grams (0.0053 wherein1 methyl or CH1 CH3 1 moles) of iodine. The reaction mixture was allowedto A Compound according to Claim 1, i y sit with the resultant formationof a red precipitate. 3,5-diphenylpyrazolium 2,4-dichlorophenoxyacetate.

The precipitate was collected by filtration, washed 3. A compoundaccording to' claim 1, 1,2-dimethylwith aqueous ethanol and air dried toproduce 3.0 3,5-diphenylpyrazolium 4-chloro-2- grams of the desiredtriiodide having amelting point of methylphenoxyacetate.

lO8-l 10C. and the following elemental analysis:

calculated: C, 32.41%; H, 2.72%; N, 4.44%; l, 61.45%

Found: C, 32.23%; H, 2.78%; N, 4.43%; l, 60.29%

1. A COMPOUND OF THE FORMULA:
 2. A compound according to claim 1, 1,2-dimethyl-3,5-diphenylpyrazolium 2,4-diChlorophenoxyacetate.
 3. A compound according to claim 1, 1,2-dimethyl-3,5-diphenylpyrazolium 4-chloro-2-methylphenoxyacetate. 